Electric switch



Oct. 25, 1938. F, J RUSSELL 2,:134207 I ELECTRIC SWITCH Filed June 22,1936 INSULATION Patented Oct. 25, 1938 UNITED STATES ELECTRIC SWITCHFrank J. Russell, Wauwatosa, Wis., assignor to Cutler-Hammer, Inc.,Milwaukee, Wis., a corporation of Delaware This invention relates toelectric switches, and more particularly to auxiliary control switchesfor use in connecti n with electromagnetic contactors and other c trolapparatus.

Auxiliary control switches having a stationary contact and a cooperatingmovable leaf spring contact which is fixed to a stationary support arecommonly employed in electromagnetic contactors to establish amaintaining circuit for the contactor uponclosure thereof. However, inpractice it'has .been found that auxiliary control switches of this typeare difiicult to adjust and are also objectionable due to the fact thatthe leaf spring contact is likely to break or become permanently bent.

The present invention has among its objects to provide an improvedauxiliary control switch which overcomes the aforementioned objections.

Another object is to provide a reliable, and efllcient control switchconsisting of a relatively small number of rugged and inexpensive partswhich can be readily manufactured and assembled.

Various other objects and advantages of the invention will hereinafterappear.

The accompanying drawing illustrates an embodiment of the inventionwhich will now be described, it being understood that variousmodifications may be made in the embodiment illustrated withoutdeparting from the spirit and scope of the appended claims.

In the drawing,

Figure 1 is a side elevational view of an electromagnetic reversingswitch having auxiliary control switches embodying the inventionassociated therewith;

Fig. 2 is a sectional view on line 2- -2 of Fig.

. and

Fig. 3 is a, diagrammatic view illustrating'the control circuits for theswitch shown in Fig. 1.

The drawing illustrates a reversing switch including a pair of 3-poleelectromagnetically operated contactors and 2 mounted side by side upona supporting plate 3. Each ofsaid contactors is provided with anoperating magnet 4, stationary contacts 5 carried by an insulating base6 fixed to plate 3, and cooperating movable contact fingers 'lyieldingly mounted upon an insulating block 8. The operating magnet ofeach switch includes a magnet winding 9 carried by a field member Illfixed to plate 3 and a verv lng part 20 located in front of said contactfinger der 28.- The leg 21 of operating member 20 is lever l3 occupiesan intermediate position and PATENT OFFICE means comprises ahorizontally arranged insulating lever l3 pivoted intermediate its endsupon a pin l4 carried by a bracket l5 fixed to plate 3. Lever l3 extendsbetween the upper ends of the insulating blocks 8 of switches l and 2and as is apparent from Fig. 2 said lever cooperates with saidinsulating blocks to prevent'closure of the contactors l and 2simultaneously.

Each of the contactors l and 2 has an auxiliary control switch i 6mounted upon its associated insulating base 6. Such switches are of likeconstruction and each includes a contact finger I! having one endmounted upon a supporting post IS, a stationary contact post I9 locatedat the opposite end of said contact finger, and an operatand carried bysaid supporting post. Contact post l9 and supporting post I 8 each havea terminal plate 2! associated therewith and said posts and theirassociated terminal plates are secured to base .6 by screws 22.Supporting post i8 is provided with a square shank 23 having a pin 24projecting from the front end thereof, and conta t finger I! is providedwith an opening for receiving said pin and is also provided with ahooked end portion 25 which engages one of the side faces of said shankto hold said contact finger against rotation upon said pin. Theoperating part 20 is provided with legs 26 and 2'l which are offsetwithrespect to each other at a point intermediate. the ends of contactfinger IT to provide a shoulprovided with an opening for receiving pin24 and said leg bears against the front face of contact finger l1 and isprovided with a hooked end portion 29 which overlaps the hooked endportion 25 on said contact finger to prevent rotation of said operatingmember upon pin 24. Contact finger l1 and its associated operating part20 are held in assembled relation upon supporting post l8 by a coilspring 30 which surrounds pin 24 and is held under compression betweenthe leg 21 of operating member 20 and a washer 3| fixed to the end ofsaid pin.

When contactors l and 2. are in open position each of the contactfingers ll of the auxiliary control switches I6 is held in engagementwith the front face of shank 23 by its associated spring 30 to disengagethe same from its associated stationary contact post l9. However, uponclosure ofeither of the contactors the operating member 20 of itsassociated auxiliary switch is moved inwardly by engagement of lever l3with the leg 26 of said operating member. During initial inward movementof operating member 20 the rear face of the leg 21 thereof is maintainedin engagement with the front face of contact finger I1 and said contactfinger is'rocked upon the edge 32 of shank I8 against the action ofspring 30 8 0 into engagement with its cooperating stationary contactpost i9. Upon continued inward movement of operating member 20 the leg21 thereof is tilted with respect to contact finger 11 against theaction of spring 30. The shoulder 28 of said operating member then bearson said contact finger at a point intermediate the ends thereof to holdthe same in closed position. Thus each of the auxiliary control switchesis adapted to be closed upon initial closing movement of its associatedcontactor, and as is apparent tilting of the operating member 20 withrespect to the contact finger l1 permits full movement of the contactorinto closed position without subjecting said finger to an excessiveoperating force.

Referring now to Fig. 3, the same diagrammatically illustrates theoperating windings of the contactors i and 2 and also the auxiliarycontrol switches associated with said contactors. A supply circuit forsaid operating windings is indicated by lines L ---L and the controlmeans therefor includes a normally closed push button 33 and a pair ofnormally open push buttons and 35. Upon depression. of push button 34the operating winding of contactor I is connected across lines L Lthrough the medium of push button 33 and upon response of said contactorpush button 34 can be released and an energizing circuit for theoperating winding of said contactor is maintained through the medium ofits auxiliary switch I6 and push button 33. Upon depression of pushbutton 35 the operating winding of contactor 2 is connected across linesL -L through the medium of push button 33 and upon response of saidcontactor push button 35 can be released and an energizing circuit forsaid operating winding is maintained through the medium of itsassociated auxiliary switch i6 and push button 33. Upon closure ofeither of the reversing contactors the maintaining circuit therefor maybe interrupted by depression of push button 33.

In connection with the foregoing it should be noted that the leg 26 ofthe operating member 20 can be bent inwardly or outwardly with respectto the leg 2! of said member to provide for closure of the contactfinger at the proper instant. Also it should be noted that the abovedescribed auxiliary switch may be modified by arranging the stationarycontact so that the same is engaged by its associated contact fingerwhen the latter is in normal position.

What I claim as new and desire to secure by Letters Patent is:

1. In a control switch, in combination, a rigid contact finger, acooperating stationary contact located at one end thereof, a fixedsupport 10- cated at the opposite end of said finger and supporting saidfinger for rocking motion into and out of engagement with saidstationary contact, a member having a part to lie against said finger,said member being supported by said finger for rocking movement relativethereto, resilient pressure means common to said finger and saidmemberbiasing said finger out of engagement with its cooperatingstationary contact and pressing said member against said finger tonormally hold the same in a given position with respect to said finger,and an operating element for moving said finger into engagement with itscooperating stationary contact by pressure exerted on said member at apoint to cause said member to rock on said finger against the action ofsaid resilient pressure means as movement of said operating element iscontinued after engagement of said finger with its cooperatingstationary contact.

2. In a control switch, in combination, a rigid contact finger, acooperating stationary contact located at one end thereof, a stationarysupport located at the opposite end of said finger and engaging one sidethereof, a member engaging said finger on the side opposite saidsupport, said finger and said member being mounted upon said support torock with respect thereto, and said member being also capable of rockingmovement on said finger, a spring biasing said finger out of engagementwith its cooperating stationary contact and pressing said member againstsaid finger to normally hold the same in a given position with respectthereto, and an operating element for moving said finger into engagementwith its cooperating stationary contact by pressure exerted on saidmember at a point to cause said member to rock on said finger againstthe action of said spring as movement of said operating element iscontinued after engagement of said finger with said contact.

3. In a control switch, in combination, a rigid contact finger, acooperating stationary contact located at one end thereof, a stationarysupport located at the opposite end of said finger and engaging one sidethereof, a member engaging said finger on the side opposite saidsupport, said finger and said member being mounted upon said support torock with respect thereto, and said member being also capable of rockingmovement on said finger, a pin mounted on said support and extendingthrough openings in said finger and said member, a spring carried bysaid pin and engaging said member to bias said finger out of engagementwith its cooperating stationary contact and to normally hold said memberin a given position with respect to said finger, and an operatingelement for engaging said member to eifect movement of said finger intoengagement with its cooperating stationary contact against the action ofsaid spring and to also rock said member on said finger against theaction of said spring as movement of said operating element is continuedafter engagement of said finger with its cooperating stationary contact.

4.-In a control switch, the combination with a rigid contact finger, ofa cooperating stationary contact located at one end thereof, a fixedsupport located at the opposite-end of said finger and engaging one sidethereof, a member engaging said finger on the side opposite saidsupport, said finger and said member being capable of rocking movementupon said' support, and said member being also capable of rockingmovement with respect to said finger, a pin mounted on said support andextending through openings in said finger and said member, a springcarried by said pin and engaging said member to bias said finger out ofengagement with its cooperating stationary contact and to normally holdsaid member in a given position with respect to said finger, and anoperating element for engaging said member to efiect movement of saidfinger into engagement with its cooperating stationary contact, saidelement exerting pressure on said member at a point intermediate theends of said fingerto cause rocking movement of said member with respectto said finger as movement of said operating element is continued afterengagement of said finger with its cooperating stationary contact.

FRANK J. RUSSELL.

